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        <p>Library Version 12.1.6.2</p>
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            <h2 class="title" style="clear: both"><a id="set_open_flags_parameter"></a>set_open_flags</h2>
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      <p>
            Initializes specific subsystems of the Berkeley DB environment. 
            </p>
      <p>
                The syntax of the entry in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> is a single line
                with the string <code class="literal">set_open_flags</code>, one or
                more whitespace characters, the method flag parameter as a
                string, optionally one or more whitespace characters, and
                the string <code class="literal">on</code> or <code class="literal">off</code>.
                If the optional string is omitted, the default is
                <code class="literal">on</code>; for example, 
                <code class="literal">set_open_flags DB_INIT_REP</code> or
                <code class="literal">set_open_flags DB_INIT_REP on</code>.  Because
                the DB_CONFIG file is read when the database environment is
                opened, it will silently overrule configuration done before
                that time.
            </p>
      <p>
            The method flag parameters are as follows:
            </p>
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          <li>
            DB_INIT_REP 
            <p>
            Enables/disables DB_INIT_REP in the DB_ENV-&gt;open method. For example:
            </p><pre class="programlisting">set_open_flags DB_INIT_REP on</pre><p>
                This enables initializing the replication subsystem. This
                subsystem should be used whenever an application plans on
                using replication.  This setting overwrites the DB_INIT_REP
                flag passed from the application's DB_ENV-&gt;open
                method.
            </p></li>
          <li>
            DB_PRIVATE
            <p>
             Enables/disables DB_PRIVATE in the DB_ENV-&gt;open method. For example:
            </p><pre class="programlisting">set_open_flags DB_PRIVATE on</pre><p>
            This enables region memory allocation from the heap instead of from memory backed by the filesystem or
			system shared memory.
			This flag implies the environment will only be accessed by a single process (although that
			process may be multithreaded). This flag has two effects on the Berkeley DB environment.
			First, all underlying data structures are allocated from per-process memory instead of from
			shared memory that is accessible to more than a single process. Second, mutexes are only
			configured to work between threads.
			This setting overwrites the DB_PRIVATE flag passed from the application's DB_ENV-&gt;open method.
            </p></li>
          <li>
            DB_THREAD
            <p>
             Enables/disables DB_THREAD in the DB_ENV-&gt;open method. For example:
            </p><pre class="programlisting">set_open_flags DB_THREAD on</pre><p>This enables the DB_ENV handle returned by the DB_ENV-&gt;open method to be free-threaded; that is, concurrently usable by multiple threads in the address space.
            This setting overwrites the DB_THREAD flag passed from the application's DB_ENV-&gt;open method.</p></li>
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